Robit released its Evolution button bit series for use in tunneling and drift applications. Testing on Scandinavian granite yielded grinding intervals up to 60% longer and a lifetime increase of 20% over conventional hard rock button bits, Robit said. The 76-mm Retrac button bit features a new face design ensuring uniform pressure distribution and efficient flushing, both of which reduce bit erosion, the company reported. The 102-mm bits were tested on hard and abrasive rock formations in Pennsylvania with results that revealed a doubling of achieved meters over previous models, the company said.
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